Back to EveryPatent.com
United States Patent | 5,010,537 |
Ohkuma ,   et al. | April 23, 1991 |
In an optical disc device, a plurality of heads provided with actuator means for inclining the direction of application of a beam applied to the surface of a disc within a predetermined range are secured onto a slider movable in the radial direction of the disc, and provision is made of detecting means for detecting the positions or the tracking errors of the beams of the plurality of heads, and slider control means for position-controlling the slider on the basis of the detection signal of the detecting means so that the directions of application of the beam spots by the actuator means are in a predetermined relation.
Inventors: | Ohkuma; Hiroya (Tokyo, JP); Sanada; Satoru (Yokohama, JP) |
Assignee: | Nikon Corporation (Tokyo, JP) |
Appl. No.: | 222036 |
Filed: | July 21, 1988 |
Jul 27, 1987[JP] | 62-187236 | |
Sep 24, 1987[JP] | 62-239797 |
Current U.S. Class: | 369/44.32; 369/53.28 |
Intern'l Class: | G11B 007/00 |
Field of Search: | 369/43-46,109,110,122,44.11,44.32,44.33,54,58,111,100,270,286 |
4167024 | Sep., 1979 | Hamisch | 369/110. |
4520472 | May., 1985 | Reno | 369/122. |
4566090 | Jan., 1986 | Eberly | 369/54. |
4578786 | Mar., 1986 | McIntosh et al. | 369/111. |
4589102 | May., 1986 | Volleau et al. | 369/46. |
4674078 | Jun., 1987 | Otsuka et al. | 369/44. |
4726004 | Feb., 1988 | Takesago et al. | 369/46. |
4761776 | Aug., 1988 | Opheij | 369/54. |
4780865 | Oct., 1988 | Yamakawa | 369/54. |
4858218 | Aug., 1989 | Takagi et al. | 369/109. |
Foreign Patent Documents | |||
61-68742 | Apr., 1986 | JP. |